The ideal shape is rectangular with rounded corners (when viewed from above) and a U-shaped or catenary-shaped bottom. This helps with water circulation and waste removal. If using an IBC tank, consider adding sand beneath the liner to create a catenary curve.
This is covered in Section 9 (Fish Tank) in The Fundamentals of iAVs. It covers the required shape, bottom profile, pump placement, and air stone positioning.
iAVs Admin Edited answer
No.
You need 1000 litres.
Would a bathttub be a suitable fish tank?
Considering they can be acquired for free..and already have a sloping/curved design for accumulating the fish manure near the drain (or perhaps the pump can be inline outside the drain/bathtub?
Hoping the tub wouldn’t need a liner? There shouldn’t be any leaching right?
I am guessing the bath tub could be placed inside the ground..or easily insulated because of its shape, above ground?